How to i do this Paula knits hats. The amount of yarn (y) in yards she needs varies directly with the number of hats (h) she will knit. The constant of proportionality is 42.

Write an equation to represent the relationship between the number of yards of yarn Paula needs and the number of hats she will knit.
What does the constant of proportionality, 42, represent in this problem?
Interpret the meaning of the point
(
9
,

378
)
in the context of this situation.